The present invention relates to an air conditioner for an occupant compartment of a vehicle having a forward vehicle space and a rearward vehicle space with one right seat zone and one left seat zone respectively. The air conditioner includes an air conditioning box, an evaporator arranged in the air conditioning box, and a heat exchanger also arranged in the air conditioning box. A cold air space is situated between the evaporator and the heat exchanger, a warm air space is arranged behind the heat exchanger, and air mixing spaces are controllably connected with the cold and warm air spaces for supplying the forward vehicle space and the rearward vehicle space with conditioned air.
In a known air conditioner of this type, in which an individual temperature adjustment for a forward vehicle space and a rearward vehicle space is possible (European Patent Document EP 0 397 997 B1), the heat exchanger is aligned transversely to the evaporator so that the cold air space adjoining the evaporator outlet surface extends below the heat exchanger and the warm air space is situated above the heat exchanger which has two outlets to one air mixing space, respectively. Each of the outlets is equipped with a swivellable air flap. The air mixing space for the forward vehicle space of the occupant compartment continues directly from the cold air space section bounded by the face of the heat exchanger facing the evaporator and can be alternatively blocked and opened up with respect to the cold or warm air space by the first air flap of the warm air space which constitutes an air mixing flap. With an increasing opening of the warm air space, the cold air space is increasingly closed and vice versa. The second air mixing space for the rearward vehicle space of the occupant compartment, which is constructed on the face of the heat exchanger facing away from the evaporator, can be alternatively blocked and opened up in the same manner with respect to the warm air space and the cold air space by the second warm air flap, which is also constructed as an air mixing flap.
On the face of the heat exchanger facing the evaporator, a swivellable cold air flap is arranged. The cold air flap bounds the cold air space section bounded by the air inlet surface of the heat exchanger with respect to the remaining cold air space bounded by the evaporator. The portion of the cold air flow, determined by the partial opening of this cold air flap, on the one hand, is supplied to the air mixing space for the rearward vehicle space and, on the other hand, is supplied to the air mixing space for the forward vehicle space. Of the cold air portion supplied to the air mixing space for the rearward vehicle space, depending on the position of the air mixing flaps, a more or less large part is guided through the heat exchanger and is available in the warm air space as warm air. The cold air flap is linked, by a rod linkage, to the two mutually coupled air mixing flaps so that a firmly defined functional relationship exists when the flaps are adjusted.
In this conception of an air conditioner, the temperature in the rearward vehicle space of the passenger compartment can be controlled only to a limited extent independently of the adjustment of the temperature in the forward vehicle space. This is because the temperature control in the rearward vehicle space is influenced by the momentary position of the cold air flap which is operated for controlling the temperature in the forward vehicle space. If, for example, the forward vehicle space is maximally heated, and the cold air flap is fully opened up, then the air mixing flap on the air mixing space for the forward vehicle compartment completely closes off the cold air space and completely opens up the warm air space, and the air mixing flap on the air mixing space for the rearward vehicle space completely closes off the warm air space and maximally opens up the cold air space. As a result, only cold air arrives in the rearward vehicle space. If, in contrast, the forward vehicle space is controlled, then various cold air flows arrive in the rearward vehicle space depending on the position of the cold air flap, and the temperature of the rearward vehicle space has to be readjusted continuously. In addition, the cold air flow for the rearward vehicle space gradually heats up on the heat exchanger, through which a continuous flow takes place, so that a cold air supply for the rearward vehicle space is impaired.
It is an object of this invention to provide an air conditioner in which an individual temperature adjustment is possible in the forward vehicle space and the rearward vehicle space of the occupant compartment without any mutual influence or reaction and additionally for the right and left seat zones, respectively.
In the air conditioner of the present invention, this object is achieved, along with others, by the provision of four air mixing spaces so that a separate air mixing space is assigned to each seat zone in the forward vehicle space and the rearward vehicle space and by the provision of a warm air flap and a cold air flap for each air mixing space for controllably connecting the four air mixing spaces to the cold air space and the warm air space.
An air conditioner according to the invention has an advantage in that, as a result of having a separate air mixing space assigned to each seat zone in the forward vehicle structure and the rearward vehicle structure and having a pair of flaps, which consists of a warm air flap and a cold air flap, assigned to each air mixing space while eliminating a double-acting air mixing flap, a completely independent and very sensitive temperature control can be achieved in the four seat zones without any mutual reaction. Simultaneously, the power of the heat exchanger is optimally utilized.
According to an advantageous development, the air flaps pertaining to an air mixing space are mutually restrictedly coupled such that one air flap will maximally open up the inlet of the air mixing space assigned to it when the other air flap completely covers the inlet of the air mixing space assigned to it, and vice versa. As a result, only a single temperature adjuster is required for each seat zone.
According to a preferred development of the invention, air passage surfaces of the evaporator and the heat exchanger bound the cold air space on opposite sides and are mutually aligned approximately in parallel, and the inlets of the air mixing spaces, which can be controlled by the cold air flaps, are arranged in pairs above and below the heat exchanger and are preferably situated in planes which are aligned in parallel or at an acute angle with respect to the air passage surfaces of the heat exchanger. This arrangement achieves a compact construction of the air conditioner and, simultaneously, avoids a constant cold air flow along the heat exchanger which is heated thereby.
According to a further development of the invention, respective air ducts branch off of the air mixing spaces for the forward vehicle space of the occupant compartment; one such air duct leads to the left outlet opening and another leads to the right outlet opening in the leg space in the front, one such air duct leads to the left outlet opening and another leads to the right outlet opening in a center plane in the front of the occupant compartment, and one cold air duct, which can be controlled by a shut-off flap, leads from the cold air space to each of the two air ducts leading to the center plane in the front. In this way, the temperature can, in addition, be lowered in the left and the right center plane of the forward vehicle space of the occupant compartment in a targeted manner with respect to the temperature in the leg space of the forward vehicle space; this is comfortable for the vehicle occupants and improves air-conditioning comfort.
According to yet a further development of the invention, one air duct branches off of each of the air mixing spaces for the rearward vehicle space of the occupant compartment; one such duct leads to the left outlet opening and another such duct leads to the right outlet opening in the center plane in the rear, one such duct leads to the left outlet opening and another such duct leads to the right outlet opening in the leg space in the rear, and one cold air duct, which can be controlled by a shut-off flap, leads from the cold air space to each of the two air ducts leading to the center plane in the rear. Such a construction permits the temperature to also be lowered in the rearward vehicle space of the occupant compartment in the left and the right center plane with respect to the temperature in the leg space; this represents an improvement in air conditioning comfort for the users of the rear seat bench.
According to an additional development of the invention, the air flaps pertaining to air mixing spaces for the rearward vehicle space are coupled with the air flaps pertaining to air mixing spaces for the forward vehicle space. Although this restricts the independent temperature control in the rearward vehicle space to certain limits, it avoids the need for separate adjusting elements for the two seat zones in the rearward vehicle space.